Chuck.



V. l. WAHLSTRGM.

CHUCK APPLmATmN mw use. 2z, :914

/ ATTORNEY UNITED STATES PATENT OFFICE.

VERNER J. VAHLSTROM, 0F BROOKLYN, NEW YORK, ASSIGNOR TO WAHLSTBOM TOOL COMPANY, OF NEW YORK, N. Y., A CORPORATION OF NEW YORK.

i CHUCK.

Specification of Letters Patent.

Patented Novutl, 1915.

Application filed December 22, 1914. Serial No. 878,477.

To all 'whom may concern Be it known that l, Vannini J. lanps'rnon, a citizen of the' United States, residing at Brooklyn, county of Kings, and State of New York, have invented a new and' useful Improvement in Chucks, of which the following is a specification.

This invention relates to an `improvement in chucks and has for its object the production of a simple device for clamping tool Shanks within a wide range of shank sizes; and the invention consists in certain parts, constructions and combinations which will be hereinafter fully described and then specifically pointed out in the claims hereunto appended.

Inv the accompanyingl drawings, which form a part of this specification and in which like characters of reference indicate the same or like parts, Figure 1 is a sectional. view of a device constructed in accordance with the invention; Figs. 2 and 3 vare crosssectional views taken on the line 2-2 in Fig! 1 showing the parts iin different positions; Figs. ,4 and 5 are 'fragmentary detail cross-sectional views also taken on the line 2 2 in Fig. 1; Fig, 6 is a detail View of ,one of the clamping jaws; and Fig. 7 is an end view of the structure shown in Figj.

The device selected to illustrate the yinvention is but one of many possible concrete embodiments thereof, and the. invention therefore is not to be restrict-ed to the precise details of the structure shown and de` scribed but is'only to be limitedby the scope of the appended claims.

Referring to the drawings, l indicates a tapered .shank, the upper part of which is broken away but is adapted to be used in connection with a. drill press or other machine tool. The shank 1 is connected by means of a pin 2 to achnek body Shaving radial slots 4 cut therein. Surrounding the body 3 is a sleeve 5*.ofl a wellknown construction having a plurality of cam surfaces 6 adapted to cooperate with jaws to be hereinafter described. The sleeve/T) is secured.to an upper vplate 7 -and a lower plate 8, both# of which are journaled upon the body 3 before referred to. Vilithin the sleeve andsurrounding the body 3 is a torsion spring 9, one end of which is secured to the body and the other end to the plate 7 in a manner wellV known in the art and clearly .disclosed in my earlier Patents Nos.

995,953, 996,954-, 996,955, 1,026,187 and 1,040,237. l

Located within the slots L.lare a plurality of clamping jaws all alike. Each of these jaws has wo integral segmental sections marked 10 and 11 of different radii, arranged to form an unbroken clamping surface, the radial centers of the section being spaced apart, as clearly indicated in Fig. 7 by means of the arrows 12 and, 13. 'At one end of the section having the smaller radius there is formed a rentrant angular recess 14, the purpose of which will be hereinafter described. Each jaw is provided with segmental ledges 15, one at each end of the section having the greater radius.

The body 3 is provided witha series of transverse slots 16 opening into the radial slots 4 before referred to, and in these transverse slots 16 are located the coils of torsion springs 17. One end of cach of these springs is pocketed in a suitable aperture 18 drilled in the body 3. The free end of each spring 17 engages one of the ledges 15 before referred to.,l Toprovide clearance for the extreme end of each spring 17 there is cut in thesleeve 5.a series of internal circumferential channels 19.

Fig. 3 illustrates the parts in their normal position. Assuming that the device is in use on a drill press which is running and it is desired to introduce a tool .shankbe-. tween the clamping jaws, the sleeve 5 1v.is grasped by the operator and stopped. This action sets up a relative rotary movement of thechuck body` and the lsleeve 5 `and the.r springs 17 then come into action to throw the clamping jaws 10-11 radially outward as theyg'xtravel down thecarn surfaces@ of7 the, sleeve. Bya'eference to FigfyQmitmill 95 be seen "that the. rentrant aingfniar recesses 14 ofthe clamping jaws 10-'-11 permitthe jaws to be thrown outwardly to the extreme limit of their outward movement and close1 into the corners formed between. adjacent p cam surfaces. lIt will be noted, too that the springs, bearing as theyl do upon tw points of the segmental ledges .15, keep the clamp! i ing jaws in vtheir normal position :is/they'V move outwardly. The tool shank having., been inserted between the jaws andl theA sleeve 5 released, the spring 9 produces a relative rotary movement between the body and sleeve in the reverse direction, and the jaws are forced inward to the tool shank rw radii and having two integral prio lthe cam surfaces v6. As soon as the jaws bite the toolshank .and the resistance of woillgis.thrown uponz thel tool, the jaws rock, iQli-ngiip )the fam surfaces and firmly Clamping the tool shank, this action being due to the action of the two segmental sections of diii'erent radii. In the event of a tool clamped! in' the 'device becoming wedged or jammed in the workfor any reason, its shank will ride off from the clamping surfaces of thejaws'lO-ll into the rentrant angular recesses Il, as shown-in Fig. v5, the result bein y thejaws will beidamaged in this emergency. When the .tool is to be released from the chuck, the sleeve 5 is again grasped and stopped which permits the springs, at this time bearingonly upon one point of the ledges as shown in Fig. 4, to move the jaws again outwardly and at the same time to turn them back to their normal position or having two integralsegmental sections of different radii arranged vto form an unbroken clampingsurface. 3. In a chuck. a cam actuated rolling jaxv having two integral. segmental sections of dii'ferent` radii arranged to form anunbroken clamping surface at one end'of the v section having the smaller radius'aiid baving a rentrant angular recess at the other end of Ythe same section.

'4. -In a' chuck, a rocking jaw having two integral, Vsegmental sections of diferent radii and two integral projecting ledges one at either end. t 'Y e 5." In a chuck, a rocking ,jaw having two integral segmental; sections of dilferent A 'ecting ledges one at either end of the section having the greater radius.

6. In a chuck, a cam actuated rolling jaw havingr `two integral segmental sections of differentii andi being of a length 'exceeding the sum of the radii.

7. In a chuck, a cam actuated rolling jaw having two integral segmental sections of different radii the radial centers of the sections being'spaeed apart.

8. In a chuck, a cani actuated rolling jaw havingiwo integral` Sglnental different. `radii the radial .centers of fw two sections being spaced apart to eww-c the adicentsirrfaces ot the two sections to form an unbrokenr clamping surface.

that neitherthe tool shank nor v and springs having torsion coils located in the transverse slots of thebody and projecting ends one .end of each spring engaging a suitable aperture in the body and the other engaging one end of one of the clamping jaws.

l1. In a chuck, the combinationl with a body having radial slots, ofclamping jaws located in sald slots each jaw having a projecting ledge ateach end, -and springs carried by A4the body each` having projecting ends engaging one of the ledges.

'12. In a chuck, the combination with a' body having radial slots, of clamping jaws located in said slots each jaw having a projectingledge at each en'd said ledge being segmental in shape, and springs carried by the body each having a projecting end engaging one of the segmental ledges and adapted to move said jaw radially outward and turn it in transit to normal position.

13. In a chuck. the combination with a body having radial slots. of rocking clamping jaws located in said slots. springsicarried b v the bodvA and each having a projecting end engaging one of the jaws, and a sleeve surroimding the body and buv-ing an internal circumferential channel cut therein to provide clearance for the free en d of the spring.

14. In a chuck. the combination with a body having radial slots. of rocking clamp- .ing jaws located-in said slots each jaw having a projectingv ledge at eachvend. a plurality of springs carried by the body each having a projecting end engagingone of vthe jaw ledges, and a sleeve. surrounding the body having a pluralitv of internal circumferential channels to provide clearance lfor the ends of the springs..

In testimony wbereof, I have signed my name to this specification in the presence of two subscribing witnesses.

VERNER J. VVAHLS'ITRO'L fifituiissest Srnxizv I. Iniisccrr, Engr/incur Louise RUSSELL. 

